DESCRIPTION (Applicant?s Abstract) The primary aim of ACTION is to determine the long-term safety and efficacy of exercise training for New York Heart Association Classes II-IV congestive heart failure patients in addition to standard of care versus a strategy of standard care alone. The secondary objective is to determine the incidence and significance of exercise-related complications. As part of this objective, the investigators will determine the specific characteristics of patients with increased benefit or increased risk from exercise. The exercise training will include 36 supervised training sessions followed by home exercise and interval supervised sessions. Training will be at 60-70% of peak VO2. Efficacy will be defined as the primary combined endpoint of all-cause mortality and all-cause hospitalizations. These clinical endpoints will be supported by physiological, resource utilization, and quality-of-life endpoints. The expected annual baseline rate is 30% for the control group. The expected dropout rate is 35% for the first year and 15%, with a cross-over rate of 5% per year. Using these assumptions, a total sample size of 3000 subjects will be required to detect a 20% reduction in the primary outcome with an alpha level of 0.05 and a power of 80%. The trial will take place over 5 years with an initial 6 months for finalizing the study and training the Regional Centers, 3 years of enrollment, 1 year of follow-up, and 6 months for close out, analysis and presentation.